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Journal Article 2004; 25(6): 415-418 PubMed PMID: 15665802 Citation  Keywords:  Aged, Aged, 80 and over, Aging:metabolism, Analysis of Variance, Cohort Studies, Humans, Melatonin:metabolism, Middle Aged, Radioimmunoassay, Saliva:metabolism,.   

OBJECTIVES: The purpose of this study was to investigate whether melatonin levels in older cohorts within the 'aged' population were significantly lower than in younger 'aged' individuals and hence point to a possible confound in cross-sectional studies which group individuals over 55 in one category.

SETTING AND DESIGN: Melatonin levels of 35 North Queensland residents over 55 years of age living in an aged-care facility, a retirement village or the general community were compared across three age groups.

METHODS: Subjects were ten 56-65 year olds, eighteen 66-75 year olds and seven over-75 year olds. Information was obtained on sleep, awakening, medical conditions and medications, with subsequent exclusion of those with known medical conditions and/or medications. Melatonin was collected by salivary samples at 2200 hours and concentrations were determined by immunoassay.

RESULTS: Mean melatonin levels were significantly lower (p=.03) in the 'oldest' (over 75 yrs) group compared to the 'youngest' (56-65 yrs) group.

MAIN FINDINGS: The results of this preliminary study indicate that within the older population, melatonin levels appear to decline significantly with age.

CONCLUSIONS: Future studies of melatonin and ageing may benefit from a longitudinal approach, with older subjects sampled across time....

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Journal Article 2003; 24(3-4): 227-232 PubMed PMID: 14523362 Citation  Keywords:  Amino Acid Sequence, Animals, Dose-Response Relationship, Drug, Enzyme-Linked Immunosorbent Assay, Hemolymph:metabolism, Leeches:metabolism, Lipopolysaccharides:pharmacology, Molecular Sequence Data, Peptides:metabolism, Radioimmunoassay, Spectrometry, Ma.   

: We demonstrate the presence in leech hemolymph of high levels of a peptide recognized by antiserum directed against bovine chromacin. The purification of the chromacin-like peptide was carried out by an acidic extraction, followed by solid phase and high pressure gel permeation chromatography and reversed-phase HPLC purification. Its sequence (GDFELPSIADPQATFESQRGPSAQQVDK) was established by a combination of techniques, including automated Edman degradation, MALDI-TOF measurement and DOT immunobinding assays with anti-chromogranin A. Mass spectrometry measurement revealed a m/z 3177Da, revealing the fact that the molecule is phosphorylated. ELISA titrations performed at each step of the purification revealed a major increase in the level of the peptide (ca. 125 nmol/microl of coelomic fluid) 15 min after LPS exposure. The increase in chromacin-like peptide levels is both time and concentration dependent. The level of this peptide decreased significantly 4 hours after LPS exposure. This report is the first discovery of a chromogranin derived like peptide in invertebrates....

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Journal Article 2003; 24(3-4): 224-226 PubMed PMID: 14523361 Citation  Keywords:  Animals, Cells, Cultured, Follicle Stimulating Hormone:metabolism, Luteinizing Hormone:metabolism, Male, Nerve Tissue Proteins:pharmacology, Pituitary Gland:cytology, Pituitary Hormones:metabolism, Prolactin:metabolism, Radioimmunoassay, Rats, Rats, Inbre.   

OBJECTIVE: Cocaine- and amphetamine-regulated transcript (CART) is widely expressed in the rat brain, especially in the hypothalamic nuclei and in the anterior pituitary. The aim of this study was to evaluate the effects of CART on pituitary hormone release in pituitary cell culture.

MATERIAL AND METHODS: The pituitary hormone release from pituitary cell culture after CART administration was investigated. Concentrations of LH, FSH, PRL, TSH and GH were measured with RIA methods.

RESULTS: CART in all doses (1 nMol, 10 nMol, 100 nMol) stimulated prolactin (PRL) release and inhibited TSH release. CART administration caused a dose dependent decrease in LH release. CART did not change GH release from cultured pituitary cells.

CONCLUSION: CART may affect directly pituitary hormones release in the cell culture....

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Clinical Trial 2003; 24(3-4): 173-180 PubMed PMID: 14523353 Citation  Keywords:  Adult, Affect:physiology, Female, Humans, Hydrocortisone:metabolism, Male, Music:psychology, Photic Stimulation, Radioimmunoassay, Saliva:metabolism, Sex Characteristics, Stress, Psychological:metabolism, Testosterone:metabolism,.   

OBJECTIVES: The aims of the present study were to examine sex-related differences in testosterone (T) and cortisol (C) changes with music listening and visual stress.

SETTING AND DESIGN: Saliva T and C concentrations were measured in 88 healthy college students (44 males and 44 females). These subjects were placed in one of 4 different conditions: (1) 30 min of listening to music, (2) 30 min of listening to music with visual stress (documentary film without sound including violent scenes), (3) 30 min of visual stress without music, and (4) 30 min of silence.

METHODS: All subjects provided two saliva samples, one collected before intervention and the other after intervention. T and C levels were assessed by radio immuno assay (RIA).

RESULTS: There was a significant difference between the sexes in the way music affected T. Music decreased T in males, whereas it increased T in females. As for C, no sex-related differences were found under any of the conditions studied. C decreased with music and increased under other conditions. THE MAIN FINDINGS: Our data suggests that the effects of music and stress on T differ between males and females.

CONCLUSION: Further investigation is necessary to evaluate the relationships between music and other substances, the effect of degree of preference and hormonal changes not only during music listening but also during music plays and creation....

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Journal Article 2003; 24(3-4): 137-140 PubMed PMID: 14523346 Citation  Keywords:  Animals, Bivalvia:metabolism, Chromatography, High Pressure Liquid, Estradiol:metabolism, Gonads:metabolism, Isomerism, Radioimmunoassay, Reproduction:physiology, Spectrometry, Mass, Electrospray Ionization, Spectrophotometry, Ultraviolet,.   

OBJECTIVES: In earlier studies, we demonstrate that 17-beta -estradiol and an estrogen cell surface receptor can be found on various human cells, i.e., vascular endothelial, monocytes, and granulocytes, where they are coupled to nitric oxide release. We further demonstrated this phenomenon in the marine mussel Mytilus edulis ganglionic tissues. In the present report we sought to determine if estrogen can be found in M. edulis reproductive tissues.

MATERIAL & METHODS: We determined the presence of 17-beta -estradiol via high pressure liquid chromatography (HPLC) and radioimmunoassay (RIA) in the animals gonads. This substance was further identified via nanoelectro-spray ionization quadrupole time of flight mass spectrometry (Q-TOF-MS).

RESULTS: 17-beta -estradiol was identified and quantified in Mytilus gonads. Interestingly, we also determined that estradiol isoforms also were present in this tissue.

CONCLUSION: These data demonstrate that 17-beta-estradiol and an estradiol isoform is present in M. edulis gonadal tissues, suggesting that they have functions related to reproduction. This further suggests that estrogen's association with reproductive activities has a long evolutionary history and that this association began in invertebrates....

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Journal Article 2002; 23(3): 239-242 PubMed PMID: 12080285 Citation  Keywords:  Adenocarcinoma:metabolism, Aged, Circadian Rhythm, Colorectal Neoplasms:metabolism, Female, Humans, Male, Melatonin:blood, Middle Aged, Radioimmunoassay,.   

OBJECTIVE: The aim of the study was pineal gland function assessment on the base of daily rhythm study and mean daily melatonin (MEL) concentrations in serum in patients with colorectal carcinoma.

MATERIAL AND METHODS: Studies were performed in 12 women at the age of 63.17+/-5.90 years and 21 men aged 58.95+/-11.32 years with large intestine adenocarcinoma. The control group consisted of 28 healthy volunteers at comparable age. During the circadian study blood samples for the measurement of melatonin (MEL) were collected every 4 hours during 12 h. MEL concentrations were assessed with the use of RIA methods. Statistical analysis of circadian rhythms of MEL was carried out with the use of cosinor method according to Halberg.

RESULTS: Existence of daily rhythm of MEL secretion was shown in all studied groups. A significant decrease of amplitude of rhythm and secretion of MEL at nocturnal hours in comparison with the control group was shown in the group of women with large intestine carcinoma. A significant decrease of mesor value and amplitude of MEL rhythm as a consequence of decrease of MEL secretion at nocturnal and morning hours was observed in the group of ill men.

CONCLUSIONS: Decrease in melatonin circadian rhythm amplitude as a consequence of its lowered nocturnal secretion occurred in all patients with colorectal carcinoma. Abnormalities in daily rhythm of melatonin secretion were more intensified in men with large intestine carcinoma, which leads to suppression of mean daily hormone concentration....

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